<div class="form-group">
    <input
        type="text"
        class="form-control form-control-user"
        maxlength="13"
        placeholder="手机号"
        name="mobileNum" >
</div>

<div class="form-group">
    <div class="input-group">
        <input 
            type="phone"
            class="form-control form-control-user"
            placeholder="验证码"
            maxlength="6"
            name="smsVerifyCode" >
        <div class="input-group-append">
            <button class="btn btn-user btn-info" type="button" id="sendSms">获取验证码</button>
        </div>
    </div>
</div>